West Ham have inserted a 20 per cent sell-on clause in the deal which will see Grady Diangana join West Brom.
The Hammers academy graduate, who won promotion on loan with the Baggies last season, will complete an £18million move to the Midlands club after undergoing a medical on Friday.
Fulham had registered late interest in Diangana but could not match the offer on the table from ex-West Ham boss Slaven Bilic and West Brom.
The deal has caused some consternation among supporters with such a promising academy product being sold, but the Hammers are well stocked in wide areas and need to raise funds for targets. West Ham started the window looking to move on Manuel Lanzini and Felipe Anderson but have not had significant interest in either with just over a week to go until they start the new campaign.
The Hammers host Newcastle on the opening day next weekend and are confident that Declan Rice will be fit and available having overcome a foot injury.
Rice is training with his England team-mates ahead of the Nations League games against Iceland and Denmark but only worked sporadically with the first team in east London before the international break.
